1. Field of the Invention
The invention relates to mechanisms for handling bank passbooks and the like. It particularly relates to mechanisms of use in receiving and positioning bank passbooks in automatic document identification and posting machines so that the book may be identified and may be updated automatically by having data posted therein.
2. Description of the Prior Art
In the prior art, passbooks have been transported into position for reading and posting by means of rollers which contact the selected front and back faces of each passbook. Pressure from the rollers is used to force the passbook along a path through the mechanism to a desired location. Problems with slippage arise with the prior art devices when an open passbook has different thicknesses at different places. Such differences in thickness occur, for example, when a ridge marking the center of the back of the passbook is parallel to the shaft, or shafts, supporting the rollers and the ridge rides between the rollers. Differences in thickness also occur when the two parts of an open passbook contain different numbers of sheets, as commonly occurs when the book is not open at the exact center. In addition, differences in thickness occur in passbooks from which sheets, or portions of sheets have been torn out by accident or design.
In the prior art, various attempts have been made to prevent slippage and the attendent misalignment. These attempts have included such steps as increasing the force provided by driving motors, using rollers which have surfaces treated to provide greater traction and using bigger rollers. None of these remedies have been entirely satisfactory from a functional standpoint. In addition, they present disadvantages, such as requiring increases in size and the cost of the rollers, driving motors and other driving means as well as presenting greater demands for energy.